In a nutshell
This study investigated whether circulating DNA can be useful for predicting the outcome of patients treated with irinotecan (Campto).
Some background
DNA is the genetic material that makes up humans. DNA can be found in cells or floating in blood (cell free DNA or circulating DNA). Analyzing the circulating DNA in patients with cancer can provide valuable information for cancer diagnosis and prognosis (predicted disease outcome). However, the previous research has focused on identifying cancer-specific markers to measure in circulating DNA. It is not clear whether simply measuring the amount of circulating DNA could be a useful for predicting patient outcome.
Methods & findings
The study included 100 patients with metastatic colorectal cancer (cancer that has spread beyond the bowel) being treated with irinotecan. 70 healthy individuals and 100 individuals with non-cancerous illnesses were also included for comparison. The circulating DNA levels were measured in blood from all 270 individuals. The patients with colorectal cancer had significantly higher levels of circulating DNA than both other groups.
Colorectal cancer patients with higher levels of circulating DNA had significantly shorter survival times. The disease progressed (continued to grow or spread) after an average of 2.1 months in patients with higher circulating DNA levels compared to 6.5 months in patients with low circulating DNA levels. The average overall survival time was 7.4 months in patients with higher circulating DNA levels compared to 13.8 months in patients with lower circulating DNA levels.
Patients were also tested for KRAS genetic mutations. Patients who had both a mutated (abnormal) KRAS and higher circulating DNA levels had shorter survival time and their disease progressed more quickly.
The bottom line
The authors concluded that measuring circulating levels of DNA could become a useful tool for predicting treatment outcomes (for irinotecan and treatments other than irinotecan) in patients with colorectal cancer.
Published By :
International journal of cancer. Journal international du cancer
Date :
May 05, 2014
